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In this issue, McWilliams and colleagues (1) report an assessment of variation in the use of imaging services for men with prostate, lung, or colorectal cancer receiving care in the Veteran Affairs (VA) health care system or Medicare. They asked, “Does a health care system with lower use of health care services exhibit less geographic variation in the use of these services?” Surprisingly, the researchers found the opposite of what they expected. Despite lower use within the VA system, they observed greater geographic variation in the use of cancer-related imaging tests within the VA system than within Medicare. Specifically, they found that both the absolute and relative differences in overall intensity of imaging services in the highest versus lowest quintiles of hospital referral regions was 240% ($247 per patient) in the VA cohort compared with only 47% ($141 per patient) in the Medicare cohort. This study provides evidence that contradicts the growing and previously untested assumption in health services research that high variation in care reflects overuse.